Circuit and method for error test, recordation, and repair

ABSTRACT

A contactor card assembly for use with a semiconductor substrate. An upper keeper plate and a lower keeper plate each include a number of conductive pins extending therethrough, situated in vias filled with an elastomeric material and extending beyond the keeper plates to contact a substrate for testing. An intermediate keeper plate is situated between the upper and lower keeper plates and includes conductive pivot bars in channels filled with elastomeric material. Each conductive pin contacts a pivot bar on one side thereof to electrically communicate with a corresponding pin on the opposite side. Under compression, variations in the height of contacts on the substrate under test are adjusted for by the movement of the pins and pivoting of the pivot bar in the elastomeric material. Methods and process for creating the keeper plates and semiconductor and testing assemblies are also included in the present invention.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of application Ser. No. 10/933,745,filed Sep. 2, 2004, which will issue on Jan. 23, 2007 as U.S. Pat. No.7,167,010. The disclosure of the previously referenced U.S. patentapplication and patent referenced is hereby incorporated by reference inits entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to methods and apparatus in thefield of probe cards and contact cards for testing semiconductorsubstrates. More specifically, the present invention relates to methodsand apparatus in the field of probe and contact cards that compensatefor variation in the height of contacts on the semiconductor substrateunder test.

2. State of the Art

For burn-in testing of semiconductor substrates, an electricalconnection must be established from the contacts on the substrate to thetesting device. Often a section of printed circuit board (PCB) withcontacts corresponding to the substrate under test is connected to thetesting device and used to make contact with the substrate. Typicallythe PCB is made of low cost PCB material, which creates difficulties inmaking it planar and also has different thermal expansion propertiesthan the substrate under test. Typically, probe cards, or contact cardshave been used to make contact from the PCB to the substrate under testto compensate for such problems.

Variation in height of the contacts of the semiconductor substrate undertest, such as where the semiconductor substrate includes mounting orinterconnect structures, including under bump metallization,redistribution lines, solder balls, or other connections, can result inprobe cards having difficulty making and maintaining good contact. Forexample, as described in U.S. Pat. No. 6,535,012, in a reusable testfixture for burn-in testing, the variation in the height of contacts ofa semiconductor substrate is compensated by a portion of the reusabletest fixture that uses contact tips or flexible contact tips forcontacting the contacts on semiconductor devices and contacts on awafer. If desired, an elastomeric mat having conductive patterns thereoncorresponding to conductive pads or contact areas on the wafer may beused with flexible contact tips on a portion of the reusable burn-infixture.

In another example, the variation in the height of contacts of asemiconductor substrate is compensated by a probe card used in a testassembly that may have a number of contact pins or needles extendingfrom it on one side that contact the PCB and an opposite set thatcontact the semiconductor substrate under test. The individual pins orneedles are typically co-planar. In compressing the testing assembly tomake contact with the semiconductor substrate under test, the probe cardmay lose co-planarity to make contact with either the semiconductorsubstrate under test, resulting in poor alignment with the opposite setresulting in the problems during testing of current leak, poorconnections, missing connections, etc.

One attempt to deal with these problems has been the use of “pogo” orspring loaded pins in a probe card. In the testing assembly, a keeperplate has a plurality of pogo pins, each pogo pin having a top side, abottom side and a central sleeve containing the springs, inserted intoholes in the keeper plate. One end of each pogo pin corresponds to acontact on the semiconductor substrate under test, while the oppositeend corresponds to contact on the PCB. Such a keeper plate can adjustfor some variation in the height of the contacts. However, each pogo pinhas a cost of approximately $1.00, and must be assembled in the keeperplate. For a wafer-sized keeper plate, between 11,500 and 12,000 or morepogo pins may be needed. As such, the costs in materials and labor tomanufacture such a keeper plate for a test assembly are significant.

Accordingly, a test apparatus or test system must have the pins in aprobe card capable of compensating of any height variations of thecontacts of a semiconductor substrate under test. Preferably, such atest apparatus or test system needs to be readily manufactured usingstandard micromachining or wafer handling techniques. Such a testapparatus or test system must be conveniently scalable from singlesemiconductor die testing to wafer-level testing.

BRIEF SUMMARY OF THE INVENTION

The present invention comprises a contact card for contacting thecontacts of a semiconductor substrate, such as a semiconductor die orwafer having a plurality of semiconductor dice for testing and burn-in.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings, which, in conjunction with the accompanying descriptionof the invention, disclose the various embodiments of the invention:

FIG. 1 is a perspective view of one embodiment of a contactor cardassembly for testing and burn-in in accordance with the principles ofthe present invention;

FIG. 2 is a side view of the contactor card assembly of FIG. 1, shown inan uncompressed condition and in relation to a semiconductor package andtester for testing of the semiconductor package, in accordance with theprinciples of the present invention;

FIG. 3 is a side view of the contactor card assembly of FIGS. 1 and 2,shown in compressed condition and in relation to a semiconductor packageand tester for testing of the semiconductor package, in accordance withthe principles of the present invention;

FIG. 4 is a side view of a semiconductor substrate, useful for forming aportion of the contactor card assembly of FIG. 1, in accordance with theprinciples of the present invention;

FIG. 5 is a side view of the semiconductor substrate of FIG. 4, having avia therein;

FIG. 6 is a side view of the semiconductor substrate of FIG. 5, whereinthe via is filled with an elastomer in accordance with one aspect of thepresent invention;

FIG. 7 is a side view of the semiconductor substrate of FIG. 6,undergoing laser ablation in accordance with the principles of thepresent invention;

FIG. 8 is a side view of the semiconductor substrate of FIG. 7 with aconductive pin inserted therein to form a portion of a conductor cardassembly in accordance with the principles of the present invention;

FIG. 9 is a side view of a substrate useful for forming an intermediateportion of a conductor card assembly in accordance with the principlesof the present invention;

FIG. 10 is a perspective view of the substrate of FIG. 9 showing achannel formed therein, in accordance with the principles of the presentinvention; and

FIG. 11 is a side view of the substrate of FIG. 10 having an elastomerdeposited in the channel thereof, in accordance with one embodiment ofthe present invention.

DETAILED DESCRIPTION OF THE INVENTION

The present invention comprises a method and apparatus for a contactorcard assembly for the probe testing and burn-in testing of semiconductordies and wafers. It will be appreciated that the invention isillustrated by the various embodiments of the invention describedherein. It will be understood that various combinations or modificationsof the disclosed embodiments of the invention may be made withoutdeparting from the scope of the invention.

Illustrated in drawing FIG. 1 is an embodiment of a contactor cardassembly 1000 of the present invention. An upper keeper plate 100includes a plurality of vias 102 therethrough. Each via 102 contains anelectrically conductive upper connector or contact pin 104 having ashaft 105, a portion (not shown) of which is surrounded by a resilient,flexible upper elastomer 106 that retains the upper connector pin 104therein, yet allows the pin 104 to move in any direction along itslongitudinal axis as the elastomer 106 flexes. Upper connector pin 104and the upper elastomer 106 are described in more detail herein. Upperkeeper plate 100 may contain holes 108 for visual and mechanicalalignment of semiconductor substrates or other structures in using theassembly 1000, including alignment of the upper keeper plate 100 tointermediate keeper plate 140 and lower keeper plate 120, as well toexternal testing device fixtures.

Similar to the upper keeper plate 100, a lower keeper plate 120 includesa plurality of vias 122 therethrough. Each via 122 containing anelectrically conductive lower connector or contact pin 124, which issurrounded by a resilient, flexible lower elastomer 126 that retains thelower connector pin 124 therein while allowing the connector pin 124 tomove in any direction along its longitudinal axis as the lower elastomer126 flexes. The lower keeper plate 120 may contain lower alignment holes128 for visual and mechanical alignment of semiconductor substrates orother structures in using the assembly 1000. Lower keeper plate 120 andupper keeper plate 100 are manufactured in the same manner from thesimilar or the same materials, differing only in the placement of theupper and lower connective pins 104 and 124.

An intermediate keeper plate 140 may be disposed between the upperkeeper plate 100 and lower keeper plate 120. An electrically conductivepivot bar 142 is contained in a resilient, flexible elastomer 144disposed in a channel 146 passing through the intermediate keeper plate140. At least a portion of the top surface 145 and bottom surface 147 ofthe electrically conductive pivot bar 142 remain exposed from theelastomer 144.

An upper connector pin 104 extending from the upper keeper plate 100contacts the pivot bar 142 on its upper surface 145, at a point alongits horizontal axis away from the midpoint of the pivot bar 142. A lowerconnector pin 124 extends upward from the bottom keeper plate 120 tocontact the lower surface 147 at a point along its horizontal axis awayfrom the midpoint of the pivot bar 142, in a direction opposite thecontact of the upper connector pin 104 on the upper surface 145. Thesupport structure 1002 for supporting the keeper plates and maintainingthe relationship therebetween is illustrated in dashed lines in drawingFIGS. 2 and 3.

Turning to drawing FIGS. 2 and 3, the contactor card assembly 1000 isshown in relationship to a semiconductor substrate 220 to be tested in atesting device 1050. A printed circuit board 200 or other testingsubstrate is mounted on an upper backing plate 204 and contains at leastone contact 202 on the surface thereof. An upper connection pin 104aligns with the contact 202 in an uncompressed position. Thesemiconductor substrate 220 undergoing testing or burn-in is disposed ona backing plate 226 located beneath the lower keeper plate 120.Semiconductor substrate 220 may be a semiconductor die, a semiconductorassembly (such as a packaged die), a semiconductor wafer containingmultiple die sites or another substrate containing an integrated circuitto be tested. An electrical contact 222, such as a solder ball on asemiconductor assembly or a bond pad on a semiconductor die, is alignedwith the lower connective pin 124 corresponding to the upper connectivepin 104 aligned with the appropriate contact 202 on the PCB 200.

As the testing device is compressed to bring the connector pins 104 and124 in contact with the electrical contact 222 and the contact 202, thecontact card assembly conforms to the contacts as illustrated in drawingFIG. 3. The upper and lower connector pins 104 and 124 are able to movein a direction along their longitudinal axes to engage the contact 202and electrical contact 222 with sufficient force to establish andmaintain electrical communication therebetween. Where the electricalcontacts 222 on the substrate 220 are of different heights, such as anarray of solder balls disposed on the under bump metallization (UMB) ofa wafer or die having variations in height across the array, contact maybe maintained in an effective manner. In some embodiments, appropriatelysized upper and lower electrical contact pins 104 and 124 may be used toallow proper contact to be made to electrical contacts 222 on asubstrate 220 that includes contact pads that have conductive bumps,such as solder balls, attached thereto and non-bumped pads, such as wirebond pads. Additionally, in some embodiments, appropriately sized upperand lower electrical contact pins 104 and 124 may be used to allowproper contact to be made to electrical contacts 222 on a substrate 220,that is a stacked semiconductor die package having electrical contacts222 on different levels of the package corresponding to the differingsemiconductor dice.

Pivot bar 142 moves within the channel 146 in response to the forcesplaced upon it by the upper and lower connector pins 104 and 124. Theelastomer 144 flexes to allow the pivot bar 142 a range of motion whileretaining it in the channel 146. As illustrated in drawing FIG. 3, thepivot bar 142 can twist, yaw, tilt or roll, in reaction to the forcesplaced upon it. Where a number of pivot bars 142 are used, eachcorresponding to an individual contact of an array, the ability of eachpivot bar 142 to act independently of the others allows contact to bemade from contact 202 to the electrical connection 222 across a varyingdistance. Compression sufficient to allow testing and burn-in of anintegrated circuit can be established, while neither PCB 200 norsemiconductor substrate 220 need be maintained in exactly parallelplanes to avoid problems from non-co-planarity of the contacts. In someembodiments of the invention, variation of up to about 100 μm can betolerated across an array of contacts. It will be appreciated that forembodiments where appropriately sized upper and lower electrical contactpins 104 and 124 are used to allow proper contact to be made toelectrical contacts 222 on a substrate 220 with bumped and non-bumpedcontact pads, or substrates 220 that are stacked semiconductor packages,this variation may refers to variations from the theoretically expectedposition of such contacts, and, even larger variations may be tolerated.

Turning to drawing FIGS. 4 through 8, one embodiment of a process inaccordance with the present invention for creating a keeper plate 420with conductive contact pins 430 extending therethrough is illustrated.A plate substrate 400 having a generally planar shape and includingupper surface 402 and lower surface 404 may be used, as illustrated indrawing FIG. 4. Plate substrate 400 may comprise any material capable ofsupporting the additional structures. For example, a substratecomprising primarily silicon, as formed in the art by growing a singlecrystal wafer in the form of a cylinder, which is then segmented orsliced, such as a wafer, may be used. Alternatively, another bulksemiconductor substrate may be employed, such as silicon-on-sapphire(SOS) substrate or a silicon-on-glass (SOG) substrate, or other type ofsilicon-on-insulator (SOI) substrate. Other substrates that may be usedas the plate substrate 400 include printed circuit board (PCB), metallicplates, ceramics or polymeric materials formed into a substrate.Additional suitable substrates may include photosensitive andmetallizable patterned glass materials, such as FOTURAN® photo-etchableglass available from SCHOTT North America, and copper coated Invar™alloy (which may be finished with gold coating). In any event, theselected plate substrate 400 may have a coefficient of thermal expansionsimilar to the testing substrate or substrate under test, to reduce thepossibility of damage during a testing and burn-in procedure.

In order to allow processing with currently available equipment, platesubstrate 400 may be a wafer or may be sized as a conventionalsemiconductor wafer, allowing for handling and processing. The platesubstrate 400 may have any suitable shape, so long as a substantiallyplanar top surface 402 and a substantially planar bottom surface 404 aremaintained. Plate substrate 400 may thus be formed as a planar disk or aplanar polygonal substrate. All such alternative structures are withinthe scope of the present invention

At least one via 406 may be formed through the plate substrate 400,extending from the top surface 402 to the bottom surface 404, asillustrated in drawing FIG. 5. The at least one via 406 may be formed inany suitable fashion known to those of ordinary skill in the art. Forexample, the at least one via 406 may be formed by laser ablation. Laserablation may be effected using any suitable equipment, such as the Model5000-series lasers, offered currently by ElectroScientific Industries(ESI) of Portland, Oreg. One specific, suitable piece of equipment is a355 nm wavelength UV YAG laser, ESI Model 2700, which may be used toform vias as little as 25 μm in diameter. One hundred pulses using thislaser will form a 750 μm deep via through silicon. Another suitablelaser is the Model 200, offered by Xsil Limited of Dublin, Ireland.Alternatively, one or more vias 406 may be formed by etching (comprisingwet etching, dry etching and either isotropic etching or anisotropicetching), by drilling or boring with a mechanical drill bit, orotherwise as known to those of ordinary skill in the art. Guide holes(such as those illustrated as 108 and 128 in drawing FIG. 1), and anyother desired structures, may be formed in the plate substrate 400 atthis time.

Once via 406 is complete, and if necessary cleaned, it may then befilled with an elastomeric material 410, as illustrated in drawing FIG.6. Any suitable elastomeric material, which may be dispensed into via406 and retain an inserted connector pin therein may be used. Thetechnique for filling via 406 will vary based on the elastomericmaterial 410 chosen. For example, a liquid elastomeric material may bedispensed directly into a via 406 and then cured. A liquid or gelatinouselastomeric material may be dispensed on the upper surface 402 of theplate substrate 400 and a squeegee or other scraper pulled across thesurface to push the elastomeric material 410 into the vias 406. Once thevias 406 are filled with the elastomeric material 410, the elastomericmaterial may be cured by baking, by photo curing or any other type ofcuring appropriate for the selected material.

Suitable elastomeric materials 410 may include electrically insulativematerial to isolate the connective pin from the plate substrate 400. Oneexample of a suitable material is liquid silicone, which may be cured toa flexible state. The cured hardness of the elastomer 410, as well asthe thickness and cross sectional are may be selected to result in aspring force on the connective pin sufficient to ensure good contact.Via 406 may be filled with the plate substrate 400 attached to anunderlying chuck plate to provide a bottom to the via 406, or may beperformed with via 406 openings exposed to allow for over-deposition ofthe elastomeric material 410, where desired. In embodiments of theinvention where the plate substrate 400 is constructed of anon-conductive material, a conductive elastomer may be used tofacilitate current flow across the substrate 400, while preventingleakage between vias 406. It will be appreciated that in embodimentswhere the plate substrate 400 is a conductive material, the conductivematerial may be used to electrically bias the final assembly to improveperformance (i.e., the material may be shorted to a ground to act as aground plane, or biased with voltage to facilitate testing).

As illustrated in drawing FIG. 7, a pin hole 412 may then be boredthrough the elastomeric material 410 contained in the via 406. As withvia 406, formation may be accomplished with a cutting laser by ablation.A micromachining laser, such as an Xsil laser, may be useful forperforming this operation. Where appropriate, the pin hole 412 may beformed by other suitable means, such as by etching, drilling or boringwith a mechanical drill bit, punching, by combining any of these meanswith each other or laser ablation, or as otherwise known to those ofordinary skill in the art. The bore of pin hole 412 has a width W. Inembodiments where pin hole 412 has a circular cross section, width Wwill correspond to the diameter of the pin hole 412.

As illustrated in FIG. 8, a conductive contact pin 430 may then beinserted into the pin hole 412, and may serve as the connector pins 104and 124 illustrated in drawing FIGS. 1 through 3. The conductive contactpin 430 may be an elongated conductive shaft 424, which will extend outfrom the plate substrate 400 to contact the structure under test and apivot bar 142. The proximal end 422 (designated as the end that willcontact the pivot bar 142) may be rounded to facilitate the movement ofthe pivot bar 142 during operation. The distal contact end of theconductive contact pin 430 may be flat, rounded, crowned, pointed, orhave any other shape that is desired and suitable for the intendedapplication. The shaft 424 of the pin may have a cross-sectional widthgreater than the width W of the bore of pin hole 412, allowing theelastomeric material 410 to retain the conductive contact pin 430 in thepin hole 412. Placement of the conductive contact pin 430 may befacilitated by use of a jig J to retain a conductive contact pin 430 inproper position during placement. Where a number of conductive contactpins 430 are used, the jig J may hold the conductive contact pins 430 incorrect alignment, allowing the insertion of the entire plurality at onetime. The protrusion of the conductive contact pin 430 from thesubstrate 400 may also be controlled by the use of the jig J, or throughmachine placement of the pin.

The conductive contact pin 430 may be constructed of any suitableelectrically conductive material. For example, a section of copper wirethat is plated with gold or a gold wire that is plated with nickel thenflash coated with a thin layer of gold may be used. In certainembodiments of the invention, the conductive contact pins 430 may beconstructed by patterning vias in a wafer or a thick resist layer andthen coating the vias with a seed layer, followed by plating the viaswith a conductive material, such as copper. The vias may be plated untilconductive material is added to form pins of sufficient depth.

One advantage of placing the conductive contact pins 430 into a bore ofa pin hole 412 in cured elastomeric material is that the conductivecontact pins 430 may be removed and replaced should failure occur.Additionally, the chance of pin contact areas becoming contaminated islessened compared to placing the conductive contact pins 430 in the vias406, followed by filling the vias with an elastomer that is then cured.It will, however be appreciated that keeper plates created using such aprocess may be used in the contact card 100 of the present invention,and as such fall within the scope of the present invention.

Illustrated in drawing FIGS. 9 through 11 is a procedure formanufacturing an intermediate keeper plate 140 including a pivot bar 142in accordance with the principles of the present invention. It will beappreciated that while illustrative of one embodiment of the presentinvention, other methods and procedures may also be used and all suchmethods are within the scope of the present invention.

An electrically conductive substrate 500 is illustrated in drawing FIG.9. The electrically conductive substrate 500 may be a planar substratehaving a top surface 502 and a bottom surface 504. Suitable electricallyconductive planar substrates may be constructed from metals. Forexample, a section of a metal foil may be provided. Other electricallyconductive substrates 500 may be constructed from electricallyconductive polymers, conductor-filled polymers, other electricallyconductive materials and combination thereof.

As illustrated in drawing FIG. 10, a channel 506 may be cut throughelectrically conductive substrate 500 to substantially surround a bar508. The bar 508 may remain attached to the substrate 500 through asmall tab 510 of material, with channel 506 surrounding the remainder ofthe bar 508. Bar 508 may have any desired shape and any desiredlongitudinal axis. For example, bar 508 may be circular, oval,rectangular, square, a regular polygon, or irregularly shaped, as isdesired for the specific usage. The upper surface 507 and lower surface509 of bar 508 may remain substantially planar, or a rounded divot 517(FIG. 11) may be placed therein for an electrically conductive contactpin 430 (FIG. 8) to slide along in a guided manner.

Channel 506 may be cut through substrate 500 in any suitable manner. Forexample, where a metal foil is provided as the substrate 500, channel506 may be cut with a micromachining laser, such as the aforementionedXsil micromachining laser, or formed by etching the foil with a suitableetchant. Where needed, the channel 506 may be cleaned to remove anydebris that would interfere with the motion electrical isolation of thebar 508. At this point the bar 508 (and substrate 500, if desired) maybe plated to improve surface hardness or conductivity. A solder maskmaterial may be used to selectively plate the bars 508.

A non-conductive elastomeric material 512 may then be disposed in thechannel 506 around the bar 508 attaching it to the substrate 500. Theupper surface 507 and lower surface 509 of bar 508 may remain free ofthe non-conductive elastomeric material 512. The non-conductiveelastomeric material 512 electrically isolates the bar 508 from thesurrounding substrate, reducing current leaking during testing andburn-in. Any suitable non-conductive elastomeric material may be used.For example, liquid silicone may be dispensed into the channel 506.Other suitable non-conductive elastomers may include flexible polymericmaterials with electrically insulative properties and flexibleinsulative epoxies.

The non-conductive elastomeric material 512 may be dispensed in channel506 in any suitable fashion. For example a liquid material may bedispensed directly into the channel 506, where the substrate 500 isplaced on a support plate providing a bottom for the channel. Forexample, a Teflon-coated plate would provide a bottom that liquidsilicone would not adhere to, allowing release. In another example, tapemay be applied over the channel and the contact portion of the bar 508,which may be removed upon dispensing or curing of the elastomericmaterial 512. Where the non-conductive elastomeric material 512 is ofsuitable viscosity, no support may be required. Where the non-conductiveelastomeric material 512 is gelatinous, or a higher viscosity fluid, thematerial may be dispensed on the upper surface 502 of the substrate 500and then disposed in one or more channels 506 by a squeegee or otherscraper.

Once the non-conductive elastomeric material 512 is disposed in thechannel 506, it may be cured in any suitable fashion. For example, thepart may be heated to cure the material, or exposed to a specificwavelength of light to photoset a photoactive material. Once theelastomeric material 512 is cured, the tab 510 may be removed to allowthe bar 508 to pivot. Tab 510 removal may occur by laser ablation,etching or as otherwise known to those of ordinary skill in the art.Where tape is applied to protect the pivot bar 508 through dispensing orhandling, the tape may be left on during tab 510 removal to protect thepivot bar 508 and elastomeric material 512 from slag and damage incurredduring tab 510 removal and then removed.

It will be appreciated that modifications to the process outlined abovemay be made by those of ordinary skill in the art. For example, anon-conductive substrate 500 may be used with vias formed therein and aconductive bar 508 placed therein to further reduce the possibility ofcurrent leakage. In other embodiments, the substrate 500 may be providedby building up a substrate 500 containing the channel through a platingprocess, such as nickel plating an appropriate mandrel, or stacking ofthick-film tab tape or fab metal. A three dimensional plated build upprocess, such a photolithography, or a controlled plating process may beused.

An entire contactor card assembly, such as that illustrated as 1000 indrawing FIGS. 1 through 3, may be assembled from an intermediate keeperplate 140, and upper and lower keeper plates 100 and 120. The contactforce of the electrically conductive contact pins 104 and 124 may becontrolled for the desired application by varying the thickness of thekeeper plates, the diameter of the pins 104 and 124, the diameter of thepin holes 412, the shape of the bar 508 and the resiliency of the curedelastomeric materials.

In other embodiments of the invention, a keeper plate 420 may beattached to a wafer or die that has solder disposed on the electricalcontacts thereof, or an assembly of wafers or dice with solder disposedon the electrical contacts thereof to form a stacked assembly withresilient contacts. This may also be accomplished with the completeassembly, including upper, lower and intermediate keeper plates to avoidthe need to form insulated vias in a package. Such an assembly may beable to undergo testing and burn-in through the attached contactorassembly. The flexible compliant contacts, formed as discussedpreviously herein, may be used in other semiconductor relatedstructures. This may be useful in any application where contact is to bemade with a array of contacts that may have variations in contactheight. For example, the contacts currently used in burn-in and testhead sockets may be replaced by the compliant connectors to add a degreeof flexibility to the contacts.

It will be apparent that details of the apparatus, processes, andmethods herein described can be varied considerably without departingfrom the concept and scope of the invention. The claims alone define thescope of the invention as conceived and as described herein.

1-11. (canceled)
 12. A keeper plate for an assembly for contacting anarray of contacts on a semiconductor substrate comprising: asubstantially planar substrate having a first surface and an oppositesecond surface; at least a first via extending through the substantiallyplanar substrate; a first elastomeric material disposed in the at leasta first via, and having a first surface substantially coplanar with thefirst surface of the substantially planar substrate and an opposite,second surface substantially coplanar with the opposite second surfaceof the substantially planar substrate; and a first electricallyconductive contact pin disposed in the at least a first via, the firstcontact pin flexibly retained in the at least a first via by the firstelastomeric material and extending beyond the first surface and theopposite second surface of the substantially planar substrate.
 13. Thekeeper plate of claim 12, further comprising: at least a second viaextending through the substantially planar substrate; a secondelastomeric material disposed in the at least a second via; and a secondelectrically conductive contact pin disposed in the at least a secondvia, the second contact pin flexibly retained in the at least a secondvia by the second elastomeric material and extending beyond the firstsurface and the opposite second surface of the substantially planarsubstrate.
 14. The keeper plate of claim 12, wherein the substantiallyplanar substrate is electrically conductive and the first elastomericmaterial comprises a non-conductive material.
 15. The keeper plate ofclaim 12, wherein the substantially planar substrate is electricallynon-conductive and the first elastomeric material comprises anelectrically conductive material.
 16. The keeper plate of claim 12,wherein the first elastomeric material comprises silicone.
 17. Thekeeper plate of claim 12, wherein the substantially planar substratecomprises a semiconductor wafer.
 18. The keeper plate of claim 12,wherein the first contact pin is removable from the first elastomericmaterial to allow replacement thereof.
 19. The keeper plate of claim 12,wherein the first contact pin comprises a gold plated copper wire, or agold wire plated with nickel and having an outer coating of gold orother conductive metal.
 20. The keeper plate of claim 12, furthercomprising an alignment via therethrough configured for alignment of thekeeper plate to an assembly for contacting an array of contacts on asemiconductor substrate.
 21. A method for forming an assembly forcontacting an array of semiconductor contacts of a semiconductor device,comprising: providing a substrate having a first surface and an oppositesecond surface; forming at least a first via in the substrate thatextends from the first surface to the opposite second surface;dispensing an elastomeric material in the at least a first via to have afirst surface substantially coplanar with the first surface of thesubstrate and an opposite, second surface substantially coplanar withthe opposite second surface of the substrate; and placing a firstelectrically conductive contact pin in the at least a first via for thefirst contact pin to extend beyond the first surface and the oppositesecond surface of the substrate.
 22. The method according to claim 21,wherein placing a first contact pin in the at least a first viacomprises placing a first contact pin in the at least a first via priorto dispensing the elastomeric material therein.
 23. The method accordingto claim 21, wherein placing a first contact pin in the at least a firstvia comprises forming a hole through the elastomeric material dispensedin the at least a first via for placing the first contact pin therein.24. The method according to claim 23, wherein forming a hole through anelastomeric material dispensed in the at least a first via compriseslaser ablating a hole through the elastomeric material.
 25. The methodaccording to claim 21, wherein the substrate is electrically conductiveand dispensing the elastomeric material in the at least a first viacomprises dispensing an electrically non-conductive elastomericmaterial.
 26. The method according to claim 25,wherein dispensing anelastomeric material in the at least a first via comprises dispensingsilicone.
 27. The method according to claim 21, wherein the substrate isnon-electrically conductive and dispensing an elastomeric material inthe at least a first via comprises dispensing an electrically conductiveelastomeric material.
 28. The method according to claim 21, whereinproviding a substrate having a first surface and an opposite secondsurface comprises providing a semiconductor wafer.
 29. The methodaccording to claim 21, wherein forming at least a first via in thesubstrate that extends from the first surface to the second surfacecomprises etching a via through the substrate.
 30. The method accordingto claim 21, wherein forming at least a first via in the substrate thatextends from the first surface to the second surface comprises boring avia through the substrate by laser ablation, mechanical drilling or acombination thereof
 31. The method according to claim 21, whereinplacing a first contact pin in the at least a first via comprisesplacing a wire in the at least a first via.
 32. The method according toclaim 31, wherein placing a wire in the at least a first via comprisesplacing a gold plated copper wire or a gold wire plated with nickel andhaving an outer coating of gold or other conductive material in the atleast a first via.
 33. The method according to claim 21, wherein placinga first contact pin in the at least a first via comprises using a jig toposition the first contact pin in the at least a first via.